Processing optical coherence tomography scans through a subject's skin comprises: receiving at least one OCT scan through the subject's skin 7, each scan representing an OCT signal in a slice through the subject's skin； processing each OCT scan so as to determine a set of parameters comprising at least a measure of the atrophy of the vascular structure in the epidermis； in which the processing produces a measurement of skin condition dependent upon each of the set of parameters, and outputting the measurement of skin condition. In another aspect an OCT image processing apparatus comprises a processor 2, a display and storage 3 coupled to the processor wherein the storage carries out the process described above. The measure of atrophy may comprise the determination of position, numerical density or volume density of blood vessels. The parameters may include skin reflectivity, skin structure as a function of depth, skin roughness or skin tone.
